Eric Casteleijn wrote: So basically using a multiple selection property in a ZClass makes that property unindexable? Wish i'd known that. The problem is my ZClass is alreday created and populated. Is there any chance of a solution other than deleting the property, adding it again as a lines or tokens type and reinserting all the values?

Hmm, couldn't you do something like http://www.zope.org/Members/kusako/AdvancedCataloging explains? i.e. just add a method to you zclass which converts the multiple selection property into the right type and returns that? And the just add the name of that method as a keyword index. cheers, oliver